1. Field of the Invention
The invention relates to a process for hermetically housing optical components, in particular for producing a housing body or parts thereof, in which preferably optoelectronic components are hermetically encapsulated or packaged, and also relates to optical components produced in accordance with the process.
2. Description of Related Art
Hermetically packaged or encapsulated housings are often used to protect sensitive components, such as lasers or photodiodes, from environmental influences and help to ensure a sufficient service life of these components.
Hitherto, glass-metal joining technologies which are known per se to the person skilled in the art and in which the housing comprises a metal component and a glass component acting as a window, which are hermetically joined to one another, have been used to produce housings/optical caps of this type.
Housings of this type often comprise a sleeve-like metal body and a glass pane which can be received in the sleeve and serves as a window. In the known production of housings/optical caps of this type, the metal and glass components were joined by means of a glass solder arranged in the form of a ring which was used as a sintered shaped part. In this case, before the components were actually joined together, the glass solder shaped part had to be produced in a separate operation using sintering technology. Then, the shaped part was inserted in an accurately fitting manner into the sleeve-like metal component and covered with the round glass pane. This was followed by the fusion operation in which sleeve and glass pane were joined to one another in a hermetic and force-fitting manner. To ensure the desired hermetic sealing of the housing, the position and shape of the glass solder between metal sleeve and glass pane in each case had to be adapted in an appropriate way. Tight tolerances have to be observed both for the housing components and for the glass solder. Therefore, considerable attention has to be paid when producing and inserting the glass solder shaped parts, which is time-consuming and expensive. Often, in particular in the case of inclined joining surfaces, it was nevertheless impossible to prevent high scrap rates, since any running of the glass solder shaped parts led to inaccurate application.
Furthermore, this technology is confronted with pronounced feasibility limits as soon as the glass window is no longer required in the form of a round disk, but rather with a polygonal contour, in particular as a right angle or in other shapes which deviate from a simple round geometry or the surface which is to be covered with glass solder is not horizontal or convex in shape. On account of their shape, there are very considerable restrictions on the glass solder shaped parts which can be produced by sintering technology, especially with the degree of accuracy required.
The conventional process is also unsuitable for optical caps, the windows of which are arranged obliquely in the metallic sleeve, on account of an excessive quantity of solder and on account of the solder ring slipping before it is melted or during the soldering operation.